Mechanism of bonding of Al-Pb alloy strip and hot dip aluminised steel sheet by hot rolling

摘要

Specimens of Al - Pb bearing alloy strip and hot dip aluminised steel sheet with intermetallic layers of various thicknesses have been successfully bonded by hot rolling. It was found that during hot rolling, two different kinds of interfaces were produced. The hot dip aluminised steel sheets and Al - Pb alloy strips were observed to bond by a mechanism of blank and block interface bonding. The effects that the dipping time, the thickness of the intermetallic layers, and the fraction of blank interfaces had on the interfacial bonding strength were investigated. The total bonding strength was found to depend mainly on the bonding strength and fraction of blank interfaces. The bonding strength of blank interfaces was four times as high as that of block interfaces. The fraction of blank interfaces increased with increasing thicknesses of the intermetallic layer up to a thickness of 73 #mu#m and decreased with increasing values of thickness above 73 #mu#m. There was a linear relationship between bonding strength and fraction of blank interfaces.